Laker<sup>3</sup>

Custom Design Tools

The Laker3™ Custom Design Tools form a unified front-to-back environment for custom circuit design and layout. They deliver a complete solution for analog, mixed-signal, and custom digital design and layout that is optimized for performance and interoperability for 28-nanometer (nm) and below design flows.

Widely-used Interoperable Custom Design FlowBased on the industry standard OpenAccess (OA) database, and with full support for interoperable process design kits (iPDKs), the Laker3 is the latest generation of the widely-used interoperable custom design flow. Laker™ is the mainstream custom design solution at leading fabless semiconductor companies, merchant foundries and integrated device manufacturers.Laker3 provides unparalleled interoperability and an open environment that enables companies to incorporate best-in-class third-party tools for analog simulation, physical verification, extraction and much more. This open system provides:

Compatibility with legacy design tools—view/edit schematics or layouts created with other OA-based tools

Integration with leading signoff tools for real-time design rule checking during layout editing

Complete support for parameterized devices written in open standard languages, such as Python, Tcl or C++

Laker3 Infrastructure

Figure 1: The Laker3 product family

Laker3 tools are anchored by a performance-driven infrastructure with ultra-fast drawing capabilities, and 2-10X faster read/write operations compared to other custom design tools. The unified binary executable of Laker3 combines design entry, custom layout, custom digital place-and-route, and analog prototyping tools into a single environment. This enables passing of design intent between tools and makes it easy to communicate design changes. Laker3 employs a modern graphical user interface (GUI) based on QT with modern features, such as tabbed windows, one-click open for recently closed designs, and configurable.

Laker Custom Layout SystemThe Laker Custom Layout System provides rule-driven and schematicdriven layout features for generating full-custom layouts in a much shorter time than manual layout methods. Its controllable automation technology simplifies the layout process while reducing verification and debug efforts.

Laker Custom Row Placer and RouterThe Laker Custom Row Placer and Router tools are ideal for automating the placement and routing of cell-based custom digital blocks that are ordinarily created by hand. Together, they facilitate rapid creation of hand-crafted quality digital blocks for mixed-signal, memory, and custom digital integrated circuits.

Laker Analog Prototyping ToolThe Laker Analog Prototyping tool automates the placement of analog devices. This improves layout productivity and provides designers with fast feedback of layout-dependent effects. It has built-in understanding of analog layout requirements, so it is much easier to adopt and deploy than competing analog automation tools.

Route-by-label function that automatically creates routes as guided by text or labels

Net router that automatically routes single or multiple nets

Advanced FeaturesThe Laker Custom Layout system uses unique technologies to exploit design rules, connectivity and parameters during layout in an efficient, consistent, and automat layout. By handling dozens of critical requirements in an automated yet natural way, the Laker layout system keeps users in complete control of the layout quality.ic way. The system's SDL capabilities save you time so you can focus on creating the best possible

Schematic-driven layoutBoth netlist and schematic views are included with the Laker layout editor for an intuitive SDL working environment. Laker SDL includes full support for hierarchical design. With Laker SDL, schematic hierarchy and layout hierarchy can be manipulated independently. Layout designers can organize the layout hierarchy in the way that works best for them while still being able to cross probe and drag and drop from the schematic.

Stick Diagram CompilerThe Stick Diagram Compiler provides users with a way to optimize device layout at a higher level of abstraction. Layout designers can swap, merge, move, spilt and align gates at a symbolic level without having to worry about design rules, connectivity or parameter values. It includes built-in automatic multi-row transistor placement capability for PMOS and NMOS transistors.

Laker Analog PrototypingLaker™ Analog Prototyping automates the placement of analog devices to improve layout productivity and provide designers with fast feedback of layout-dependent effects. The tool's built-in understanding of analog layout requirements makes it much easier to adopt and deploy than other analog automation tools. As part of the complete Laker3 Custom Design family, the analog prototyping tool brings together the award-winning Laker schematic-driven layout features with significant advancements in automation to speed completion of custom analog layout.

Analog Prototyping FlowAnalog prototyping in the Laker environment starts with an analog schematic or netlist. Laker Analog Prototyping analyzes your circuit and automatically generates placement constraints that drive the automatic placement engine to create high-quality placement results. The placement engine generates multiple example placements all of which meet the design onstraints. From there, users can refine the constraints as needed until reaching the desired placement. With the ability to rapidly complete the placement of analog circuits, you can generate early placement results for circuit designers to use for layout-aware simulation.

Figure 7: Analog prototyping flow

Core FeaturesLaker Analog Prototyping combines all of the Laker SDL features with advanced automation capabilities that include:

Automatic constraint extraction

Design rule checking engine with advanced-node rule support

Pattern editor for placement and routing of matched devices

Automatic constraint-driven placement

Hierarchical analog prototyping

Figure 8: Laker analog prototyping

Automatic Constraint ExtractionGenerating proper constraints is an important part of the analog prototyping flow. Laker Analog Prototyping automates this process with an automatic constraint extraction engine. This engine identifies devices that have symmetrical current flows and forms them into symmetry groups. It also recognizes common subcircuit types, such as differential pairs, current mirrors, voltage references, etc., and automatically forms them into matching device patterns. In addition, it finds and forms digital logic into transistor chains with properly-aligned gates. The Laker hierarchical constraint browser permits easy review and editing of the constraints in a design. Laker supports the iPL standard iConstraint format.

Design Rule Checking EngineLaker Analog Prototyping includes the full version of the Laker DRC engine with advanced node support. This engine is used by the Laker placement engine to create design-rule correct placements and substantially improve rule-driven layout editing as compared to basic rule-driven editing operations. Any design rule can be checked dynamically during editing, not just the basic width and spacing rules. After a shape is added, any design rule errors that Laker detects are displayed with fixing guides that illustrate how an error can be corrected. The DRC engine can work directly from the Laker technology file for many of the design rules, so no special rule file is required.

Figure 9: Laker interactive Design Rule Checking

Pattern Editor for Placement and Routing of Matched DevicesOne of the most powerful productivity-enhancing features in Laker is the matched device creator, a symbolic pattern editor for handling matching devices. Users can draw from the built-in Laker pattern library to apply matching placement patterns to devices, for example, placing a differential pair in a common centroid configuration. The pattern library can be extended with user-generated custom patterns of device placement. Laker Analog Prototyping also features matched device routing capability. With the matched device router, users can automatically generate routing patterns for matched device. If needed, users can modify the routes generated by the matched device router by simply dragging and dropping the wires to a new location. When the pattern is instantiated into the layout, DRC-correct wiring is included.

Automatic Constraint-driven PlacementThe automatic constraint-driven placement in Laker Analog Prototyping is capable of meeting a variety of analog constraints, including symmetry, matching, cluster, spacing and variation constraints. It generates multiple solutions so users can explore a variety of potential solutions.The placer uses the built-in LiveDRC design rule checker to generate designrule- correct placements. It also checks for routability using a built-in trial router and adds space between components as needed to create a routable placement. The placer can also enforce constraints related to layout-dependent effects (LDE). Pin placement can be handled automatically, or it can be taken from the pin locations in the schematic or from a floorplan layout. The floorplan layout can also be used to preplace critical devices. The placer maintains the relative locations of preplaced devices from the floorplan when placing the remaining devices.

Hierarchical Analog PrototypingHierarchical prototyping is supported with the Laker physical hierarchy manager. The hierarchy manager GUI shows the block present in a design and allows users to configure the constraint extraction and placement settings for each block. During hierarchical placement, multiple potential solutions are generated for sub-block use in the next level in the hierarchy with only the best solutions preserved. This process continues until the top-level hierarchy is reached. With Laker hierarchical analog prototyping, designs with thousands of devices can be placed in just minutes.

Laker Custom Row PlacerThe Laker Custom Row Placer provides automation for the placement of custom digital cells that would normally be placed by hand. It allows precise custom placement of the digital blocks used in mixed-signal and custom digital designs.

Automatic and manual addition and removal of filler, well tap, and end cap cells

Laker Custom Digital RouterThe Laker Custom Digital Router is ideal for automating the routing of blocks that are normally routed by hand, such as the control logic sections of memory designs. It features:

Unique hybrid routing technology that combines gridded and shape-based routing for very high route completion rates while being DRC clean.